1. Field of the Invention
The present invention concerns a harvesting head for small fruit produced on hedges, in particular in orchards. It also concerns the self-propelled straddling vehicles used for its application, i.e., the assemblies constituted by a self-propelled straddling vehicle carrying a harvesting head mounted to the rear of the chassis of this vehicle.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
Nowadays, for harvesting olives grown in fruit hedges, certain olive-growers use machines of large dimensions similar to grape-harvesting machines, particularly in regions where vines are cultivated on relatively high trellises (in the order of 2 m).
These machines feature a harvesting head comprising generally a shaking system including two fruit-detaching assemblies that are mounted opposite each other and separated by a vertical space, these assemblies featuring each a number of stacked shakers, for example consisting of flexible bars attached, through the intermediary of their ends, to two vertical shafts, of which at least one is an oscillating actuation shaft linked to a shaking control so as to impart it an oscillating movement. Such a harvesting head also includes two lateral conveyor systems to receive and transport the picked fruit to a receiving device (bin or other), the horizontal portions of these transporting systems ensuring also tightness around the low part of trunks (vine-stock), below the shaking assemblies.
The harvesting head is solidly mounted on the rear part of the chassis of a self-propelled straddling vehicle which can be equipped with means to raise or to lower it between a low position for road-transport and a high working position. In this case the harvesting head is fixed to said chassis and goes along with its raising and lowering movements.
One drawback of these machines, whatever their intended use, is their large dimensions (in the order of 3.0 m wide and 4.0 m) high, which poses problems for their transport on a flatbed truck or their movements over the road, to go from one plantation to another.
However, the main constraint imposed by the machines presently in use consists of the clearance under the arch of the straddling vehicle, the height of which may vary between 2.20 m and 2.80 m and the capabilities of a threshing head to shake a fruit-bearing hedge instead of a trellised vine, the active part of this threshing head being about 1.80 m high.
The fact that one has available a threshing height of 1.80 m and an arch clearance of a height of 2.20 m, obliges the driver of the harvesting machine to adjust the straddling vehicle in the high position (2.80 m) to allow the fruit-bearing trees (olive-trees for example) to pass without breaking them, but the problem that arises then is that the lower tightness system of the harvesting head which is integral with the movements of rising and lowering of said straddling vehicle is fully immersed in the vegetation, on the branch level, instead of tightening around a tree trunk, this causing significant losses of fruit dropping to the ground, heavy breaking of branches and leaving in place, at the same time, on the low part of the trees, all the fruit that did not come in contact with the picking arms of the harvesting head.
In the opposite case, if the driver operates the straddling vehicle in its lowest position, so as not to leave behind any fruit and to prevent any fruit from falling to the ground, the olive-trees (in the case of an olive-grove) which have a height above 2.20 m are going to be forced to pass under the arch of said straddling vehicle at the risk of breaking them at ground level.
On the other hand, if in spite of everything, the olive-trees manage to twist without breaking to pass under the arch of the straddling vehicle (2.20 m) the harvesting head (1.80 m) is going to leave all the fruit that is on the upper portion of the trees when the fruit passes into the harvesting head and to ruin a great part of it with the threshing mechanism.
There are also hybrid machines designed for the harvesting of grapes and olives which are in fact customized grape gathering machines with an arch in the order of 2.40 m to 3.0 m and a threshing height of 2.0 m to 2.8 m. For the time being these are the only ones operating effectively in olive orchards.
A major drawback of these machines is that they are extremely large to mitigate the constraints of the standard grape-harvesting machines mentioned above.
So, this type of machine is higher, larger, longer, heavier, and more expensive. Its versatility becomes questionable as soon as one wants to pick grapes; because of its oversized dimensions, this type of machine is no longer really suitable for vineyards, because it is practically impossible to turn the machine around at the end of a row during the vine-harvest.